Sealed oscillating member or armature of polarized electromagnetic relay or switch



.JanQIZ', 1960 M, SCATA m1 2,921,161

SEALED OSCILLATING MEMBER OR ARMATURE OF POLARIZED I ELECTROMAGNETIC RELAY OR SWITCH File d sept. 9, 1957 2 Sheets-Sheet l Inventor 3. Dal 312111 :0 M. five- 21.

' Agent Jan. 12, 1960 M. SCATA ETAL 2,921,161

SEALED OSCILLATING MEMBER OR ARMATURE OF POLARIZED ELECTROMAGNETIC RELAY OR SWITCH 2 Sheets-Sheet 2 7 Filed Sept. 9, 1957 FIG.6.

FIGS.

SW65 Pa e SEALED OSCILLATING MEMBER OR ARMATURE OF POLARIZED ELECTROMAGNETIC RELAY OR SWITCH Mario Scata, Monza, and Bruno Dal-Bianca, Milan,

Italy, assignors to International Standard Electric Corporation, New York, N.Y., a corporation of Delaware Application September 9, 1957, Serial No. 682,654 Claims priority, application Italy September 11, 1956 8 Claims. (Cl. 200-87) This invention relates to electromagnetically operated relays or current and voltage switches and more particularly to a movable member of a polarized relay carrying electric contacts, the whole enclosed in a protective vessel.

One of the objects of this invention is to provide a relay which is economical of manufacture, easily replaceable when the parts become defective, of high efiiciency and sensitivity in operation and rapid in closing and opening the circuits which its contacts control.

One of the main features of this invention is to have enclosed a balanced oscillating armature and its contacts within a protective vessel, air evacuated or filled with an inert gas; the permanent magnetic field for balancing the armature and the energizing coil of the relay being disposed outside said protective vessel.

Another feature of the invention involves the particular shape of the movable balanced armature which minimizes the gaps of the magnetic circuit and thereby reduces the dispersion of permanent and variable magnetic fluxes.

A further feature of the invention is to provide a manufacturing method permitting a considerable saving in material. This is obtained by a simple design and using a limited number of piece parts, in addition to eliminating costly material. The speed in fabrication is also obtained by the use of normal processes adopted for the usual relay manufacture and with a very simple assembly of the central resilient element on opposite sides thereof and.

spaced one from the other to permit a slight movement Within the cylindrical vessel, said bars being clamped to said element at a point near to the center of gravity of the oscillating system.

Another feature of this invention is to provide a support for the movable armature by means of a single resilient metal strip which is firmly clamped on the center of gravity of the movable magnetic element, such a strip having the movable contact(s) fastened by riveting or other suitable means adjacent one end thereof and having the other end extending through a sealed end wall of the vessel, a portion of the length of the strip, comprised between said end wall of the vessel and a line passing through the center of gravity of the oscillating armature, being clamped between two mounting elements oppositely positioned which, when introduced into the vessel, keep the system self-centered within the vessel itself and limit the length of the bending portion of the supporting strip itself.

. An alternative to the type above described and. to the type described in Belgian Patent No. 559,769 issued on ing armature, formed, as in the preceding embodiment,

by two small bars of magnetic material, joined together in the center and spaced therebetween, is supported at the center of gravity by pivots formed by a resilient strip surrounding the armature in the middle of its length and clamped partially by the same rivets, joining the two straight bars and the spacers, whereas the other portions of the resilient strip have at the center two spherical protuberances which abut against the internal wall of the vessel and which serve as pivots for the oscillating armature.

The above and other features and objects of this in-' vention will be more clearly understood by referring to the accompanying drawing in which:

Fig. 1 is a longitudinal front section of a first embodiment of the invention showing the mounting of the elements in its interior and the external magnetic system which cooperates therewith;

Fig. 1A is an end cross-section of the structure shown sembly of the movable member of the type shown in Fig. l and its springy support ready to be introduced in the vessel;

Fig. 4 shows the detail of one of the stationary contacts soldered to a Wire sealed at one end of the vessel, the

- contact being made with a rectangular small bar instead February 3,' 1958, in a further embodiment, the oscillat- 1,

of one hemisphere contact; Fig. 5 is an enlarged longitudinal section of another embodiment of the invention wherein the armature assembly is pivoted against the side wall of the vessel;

Fig. 6 shows the cross section of Fig. 5 along the line b-b;

Fig. 7 illustrates the cross section of Fig. 5 along the line c-c; and

Fig. 8 is an enlarged view of an assembly in PBI'SPCC'. tive of an oscillating member or relay armature, ready to be placed inside the vessel.

Referring now to Fig. 1 the electromagnetic switch comprises a sealed vessel 1 made of glass or some suitable non-magnetic material. The armature assembly consists of a pair of spaced parallel bars 2, 3, made of magnetic material and having a cross-section similar to a sector of a circle. These bars are mounted on a long, flat, spring element 4 made of non-magnetic material. Adjacent one end of the element 4 are the movable contacts 5. The element 4 is fastened at its other end to the terminal 6 which extends through one end wall of the vessel 1. Adjacent the contacts 5 are a pair of fixed contacts 7, 8, which contacts are mounted on leads 9 and 10 which extend through the opposite end wall of the vessel 1. The armature assembly is coaxially positioned with respect to the interior of the vessel 1 by means of a pair of U-shaped elements 11 and 12 made of non-magnetic material which elements are situated back-to-back and which clamp the spring 4 between them. Details of this clamping may be ap preeiated from Fig. 1A. The arms of "the U-shaped elements 11 and 12 are adapted to abut against the inside wall of the vessel land have suflicient resilience to maintain the assembly firmly positioned within the vessel. The bars 2 and 3 are attached to the element 4 through spacing blocks 13, 14, disposed on opposite sides of the element 4 and the elements 2, 14, 4, 13 and -3 are fastened together by means of rivets. 15 and 16. It will be noted that the bars 2 and 3 fit within the troughs defined by thearms of the U-shapedmembers 11 and 12 with sufficient clearance to enable them to move freely therein. The point of attachment of the bars 2 and 3 to the element 4 corresponds to the center of gravity of said bars. To .inhibit contact bounce of the movable contact .5, there is provided a mass of elastic material 17 surrounding a portion of the element 4adjacent the ends of the bars 2 and 3 and which material 17 wedges the element 4 between the ends of said bars, as shown in Fig. 1. The elastic material may be silicon, as 'shown inFigs. 1 and 3 or it may constitute two oppositely disposed spring elements 19 and 20, shown in Fig. 2. In either embodiment the element 4 is maintained centrally positioned between the bars 2 and 3. As shown in Fig. 1, there iswound about theexterior of the vessel 1 an energizing winding .21. There is further disposed exteriorly of the envelope, permanent magnets 27 30 and which magnetsare positioned adjacent the ends of the. bars 2 and 3 and .in planes normal to the. axes thereof. Thus, with the energization of the winding 21, the flux developed by the several magnet systems 27 30 is'balanced and, consequently, the armature assembly within the vessel remains centered, as shown in Fig. 1. current will cause movement of the armature, since the flux balance is upset. Energization of the coil 21 in an opposite direction will cause the armature to move in a i'everse direction since the flux balance is upset in such opposite direction.

In Fig. 4 there is shown an alternative form given to the fixed contacts 7'8, this shape being similar to a rectangular bar in order to eliminate the action of the external magnetic field over the te1'minals 910, generally made from magnetic material to match the expansion coeificient of the vessel glass.

' Figs. through 8 disclose another embodiment of the invention and wherein the-armature assembly is pivoted in its center of gravity and against the inside wall of the vessel. The contact assembly of the modification in Figs. 5-8 is identical with that of Figs. 1, 2 and 3. In the embodiment of Fig. 5,- however, the element 4 is again clamped between two U-shaped members 25 and 26 but which members are of relatively small length as compared -to the members 11 and 12 of Figs. 1 and 3. The bars 2 and 3 are againspacedly mounted in parallel to the element 4 by means of the spacing blocks 13 and 14 at a point corresponding to the center of gravitation of the system, but in this embodiment the rivets 15 and 16 also include a band 22 which surrounds the elements 2, 14 4-, 13 and 3, as shown in Fig. 8. Disposed on opposite sides of the band and normal to the longitudinal axis of the armature system, are a pair of protuberances 23 and 24. These protuberances areadapted to be urged by the resilience of the band 22 against diametrical portions of the inside of the wall of the vessel, as shown in Fig. 5, and the system is adapted to pivot thereon. It will be noted that the axis of the protuberances 23 and 24 is also normal to the planes of the magnet system 27 30. In thisembodiment, the structure may be prefabricated, as shown in Fig. 8, and then inserted into the vessel 1. The legs of the elements 25 and 26 will center the armature system with respect to the axis of the interior of the vessel 1, and the protuberances 23 and .24 will abut against the inside of the wall of the vessel .1 and the system will pivot therearound. The antibounce springs 19 and 20 will serve to absorb the rebound, as explained previously with respect to Figs. ,1, 2 and 3.

-In assembling the relay, the fixed contacts 7 and 8 are first mounted on their supports 9 and and the sup- .ports are .fusedin one end wall of the vessel. Thereafter; the structure of Fig. 8 is inserted from the other Energization of the winding 21 by a direct envelope and/ or filling it with inert gas which will inhibit arcing at the contacts. I

The adjustment of the balance of the movable armature is then improved by driving away or approaching the pole pieces of the permanentjmagnets 2728-'-29- 30 surrounding the vessel (Figs. 1 and 5), andplacing near the" ends of the'bars 23, the path of the magnetic permanent flux throughout the armature, its action thereon and the operating means, being the same as those described in said Belgian patent.

While the principle of this invention has been described above in connection with two specific embodiments as actually manufactured, it is to be clearly undercould be covered by other practically mechanical shapes,

end of the vessel which is then sealed so that the terwithout departing from the scope of this invention.

What is claimed is:

l. A magnetically operated switch device comprising a closed vesselhaving opposite end walls and a side wall, said vessel being of non-magnetic material, fixed contact means extending through a first end wall of said vessel,

armature means within said vessel, said armature means comprising a resilient element made of non-magnetic material, electrical connecting means extending through the other end wall of said vessel and connected'to a first end of said resilient element, contact means attached to said resilient element adjacent the other endthereof, said lastmentioned contact means adapted to cooperate with said fixed contact means, a pair of bars of magnetic material positioned parallel to each other and to said resilient element,'means for fastening said bars to opposite surfaces of said resilient element at a point intermediate the ends thereof and which point corresponds to the center of gravity of said bars, means for mounting said resilient element and said bars coaxially with respect to the interior of said vessel, said mounting means connected to' said resilient element at a point intermediate the first end of said element and the point at which said bars are connected thereto, said mounting means being of non-magnetic material and abutting against different portions of the side wall of the interior of said vessel, magnetic means external of said vessel in proximity to the ends of said bars and normal to the axes thereof, for maintaining said armature means in a state of magnetic balance, and an operating winding position about the outside of said vessel intermediate the ends of said bars for altering said state of balance upon application of an electric potential to said winding whereby the position of the contact means associated with said. armature means is altered with respect to said fixed contact means.

2. A magnetically operated switch device as claimed in I claim 1, wherein said vessel is circular in cross-section and said bars have a cross-section of a sector of a circle whose diameter is less than the diameter of the interior of said vessel.

3. A magnetically operated switch device as claimed in claim 1, wherein said means for fastening said bars to opposite surfaces of said resilient element comprise a pair of like spacing blocks disposed on opposite surfaces of said resilient element, each of said bars mounted atop a different one of said spacing blocks and fastening means extending through both said bars, said blocks and said resilient element.

4. A magnetically operated switch device as claimed in claim 1, wherein said means for mounting said resilient element and said bars in the interior of said vessel cornprises a pair of channel-shaped members, positioned oppositely on opposite sides of said resilient element with the arms of the channels extending in opposite directions, the distance between the edges of corresponding opposite arms of said members being substantially equal to a chord of the cross-section of the interior of said vessel.

' 5; A magnetically operated switch device as claimed in claim 4, further comprising means for fastening said channel-shaped members to said resilient element.

6. A magnetically operated switch device as claimed in claim 1, further comprising anti-bounce means fastened to said element adjacent the point of attachment of said contact means, said anti-bounce means in contact with corresponding surfaces of said bars, whereby said resilient element is clamped.

7. A magnetically operated switch device as claimed in claim 1, further comprising pivoting means attached to said bars at a point corresponding to the center of gravity thereof.

8. A magnetically operated switch device as claimed in claim 7, wherein said pivoting means comprises a flexible band wrapped coaxially around said bars and said resilient 15 2,383,973

element, said band having a pair of oppositely disposed protuberances extending outwardly therefrom in a plane normal to the axes of said bars and to the direction of movement of said bars and said resilient element, the distance from tip to tip of said protuberances corresponding substantially to the diameter of the interior of said vessel.

References Cited in the file of this patent UNITED STATES PATENTS 1,984,505 Walker Dec. 18, 1934 2,245,391 Dickten June 10, 1941 2,264,022 Ellwood Nov. 25, 1941 Jones Sept. 4, 1945 

